New media events have become an important topic of research that explores the influence of the Internet on Chinese society. This quantitative study applies the collective memory theory, the emotion theory, and the discourse opportunity theory to examine new media events. The users of social media are also the writers of collective memory, and the discourse on social media could be seen as comprising the text of collective memory. When people discuss a specific new media event, they express their own emotions, which they share with their social networks online. We built a new media event database including 262 important new media events from 2002 to 2014, and we coded the types and outcomes of the events. We then collected data from Sina Weibo using the keywords of the events on Python. We used LIWC, a software that is widely implemented in sentiment analyses, to obtain interesting findings. First, the more that a specific event was reported by conventional media, the more it was discussed on social media. Second, different types of new media events produced different impressions and emotions in the collective memory. Specifically, events that were characterized by citizen advocacy and nationalism were the most likely to elicit positive emotions. Accidents, disasters, and events related to food and drug safety were the most frequently mentioned. Events that were related to crime and social security were the most likely to provoke negative emotions, especially anger and anxiety. Accidents and natural disasters elicited the most sadness in the collective memory. However, new media events caused by structural contradictions or the injustice of the society were not discussed frequently, which was an unexpected finding. The results suggest that people care more about the events that are close to their daily lives than events that reflect social problems. The results also indicated that topics about social structure or social institutions are politically risky, which reduced the amount of related discourse on social media. Furthermore, the outcomes of new media events were also related to emotions in the collective memory. When the events caused the death of people or changed the policies or decisions of the government, they raised feelings of anger in the collective memory, while the fall of officials reduced such feelings. Anxiety existed in the collective memory of events caused death or imprisonment. The events that increase social support elicited sadness in the collective memory although the outcome was positive.